//
//  MainTabBar.swift
//  SinaWeibo
//
//  Created by bot on 16/5/13.
//  Copyright © 2016年 bot. All rights reserved.
//

import UIKit

class MainTabBar: UITabBar {
  
    //懒加载中央的button
    lazy var composeBtn: UIButton = {
        
        let btn = UIButton(type: UIButtonType.Custom)
        btn.setBackgroundImage(UIImage(named: "tabbar_compose_button"), forState: UIControlState.Normal)
        btn.setBackgroundImage(UIImage(named: "tabbar_compose_button_highlighted"), forState: UIControlState.Highlighted)
        btn.setImage(UIImage(named: "tabbar_compose_icon_add"), forState: UIControlState.Normal)
        btn.setImage(UIImage(named: "tabbar_compose_icon_add_highlighted"), forState: UIControlState.Highlighted)
        
        btn.sizeToFit()
        return btn
        
    }()
   
    override init(frame: CGRect) {
        super.init(frame: frame)
        self.setupUI()
        
    }

    required init?(coder aDecoder: NSCoder) {
//        fatalError("init(coder:) has not been implemented")
        super.init(coder: aDecoder)
    }
    
    private func setupUI() {
        addSubview(composeBtn)
    }
    
    //对button的frame进行布局
    override func layoutSubviews() {
        super.layoutSubviews()
        
        let w = bounds.size.width / 5
        let h = bounds.size.height
        let rect = CGRectMake(0, 0, w, h)
        var index:CGFloat = 0
        
        for subview in subviews {
            
            if subview.isKindOfClass(NSClassFromString("UITabBarButton")!){
                
                subview.frame = CGRectOffset(rect, w * index, 0)
                
                index += index == 1 ? 2 : 1
            }
        }
        
        composeBtn.frame = CGRectOffset(rect, 2 * w, 0)
//        composeBtn.frame = CGRectOffset(rect, 2 * w, -20)
//        bringSubviewToFront(composeBtn)
    
}

}
